When settlers moved into the desert west a century or so ago and started irrigating crops, they created new habitats for some species that Mother Nature had held in check. Species such as Mormon Crickets became pests, overwhelming the irrigated crops produced in the unnatural habitats and plaguing their human guests.¹

The same goes for the Sacramento pikeminnow. The dams and farmland reclaimed from wetlands in California’s Central Valley have created ideal habitat for the pikeminnow. Pikeminnownow have become so abundant they have become predator nuisances that feed on ever-decreasing numbers of young salmon and steelhead. Pikeminnow also migrate from the Delta to spawn in valley rivers below dams where they prey on young salmonids. Juvenile pikeminnow compete with young salmonids for aquatic insects and feeding territory.

The problem also occurs on the Eel River, a large coastal salmon river that once featured some of the largest salmon and steelhead runs in California.² Sacramento pikeminnow are not indigenous to the Eel River: they were introduced by anglers who brought “minnows” to use as bait to fish for trout stocked in PG&E’s Lake Pillsbury on the Eel River’s mainstem.

There are three ways to deal with the pikeminnow problem. One is to selectively eradicate them. The Columbia River water folks tried this first approach for decades now – that has not worked.³ The Eel River folks are trying weir traps.⁴

Another approach is to reduce the habitat conditions that allowed enables the high production of pikeminnow in the first place. Replacing warm, slow-moving pools with colder, faster-moving water makes habitat less conducive to pikeminnow.

A third approach is allowing salmon and steelhead to get to places the pikeminnow are not. Many organizations are seeking the removal of Scott Dam, which creates Lake Pillsbury. This will allow salmon and steelhead access to the Eel River upstream of the current lake. There are natural barriers upstream that steelhead and salmon can pass but that pikeminnow, which are weaker swimmers, cannot.

To help recover our native salmonids in the Central Valley, a combination of weirs and colder water, reverse engineering the habitat to reduce pikeminnow production, and the reintroduction of salmonids in higher elevations too cold for pikeminnow could be the recipe for success.